The experience of Ortygia ()
Introduction
In the present lexicon of the Italian language for "code" is intended, generally, a harvest of laws that concerning with a particular sector or, also, a specific relative legislation to a determined branch of the law. According to such lexical interpretation the "codes of professional practice" can be considered to the same of antiseptic containers of norms, of ties, of prescriptions or as a whole of pre-parcelling models or of rigid standards (more suitable for the realization of new constructions).
In the today's professional practice, to the abundance of handbooks and manuals rich in predefined solutions or of rigid typologies of intervention, it corresponds progressive planning annihilation of numerous technicians that transform the former conservative intent, realizable exclusively through "culturally and critically technical aware actions", in a daily routine of uncritical transformations inevitably forgers and destructive.
To avoid these risks the professional updating should be effected with tools able to offer an wide "code of reading", not only on the values proper of the ordinary building and on the most correct formalities to realize the conservative intervention, but above all on what and how much the specificities are proper of every historical town, of every building compartment and of every single building; everything this always conscious that the act of the conservation is contemporarily historical-critical judgment and technical-scientific knowledge and that in it humanistic and diagnostic-operational circles are understood.
Interpreting the lexicon of the word "code" in the widest sense of a system of signs, conventional and symbolic, able to transmit an information, or of a whole of linguistic and stylistic elements that characterize the building system in examination, it can be reached to an harvest of deprived rules of legislative but rich value of different content resulting from the local customs and from the "done properly".
As in the case of the search on the façade of the ordinary historical buildings in Ortigia, needs to consider the pre-existences systematically studying them in their historical and technical values, paying the due attention to the structural typologies, to the constructive systems and to the nature of the materials, identifying most recurrent pathologies in relation to the particular environmental state and examining, finally, the complex aspect of the yard and the realization of the work. It's necessary, also, with the help of the most actual addresses of method, to analyse the possible technical solutions appraising the merits and their lacks, constantly comparing the traditional systems with the most actual techniques of intervention.
It's clear that such a study, although inspired to methodological addresses and to general criteria, could furnish exclusively only a limited number of valid suggestions within the geographical limits of the site in examination.
We know that the planner of the conservation develops an comparable extremely delicate assignment, for some verse, to that of "a director or of a manager of orchestra", of "good family doctor" that makes an attempt expert of the history (not only clinic) of every single patient can to address him toward consultations more deepened. Who writes, thinks more correct the reference to the figure of the "homeopathic doctor" that, through the use of small doses of specific substances, adapts the care to the patient looking well from following preconceived schemes of cares for typologies of illness.
Except rare examples the professional practice is well different: the unconditional technical development, the increased economic interest toward the historical building, the continuous state of emergency in which too many historical environments, especially in southern Italy, pour, jointly to the continuous proliferation of unknown effectiveness materials and techniques, constitute precise factors of danger and deterioration of some cultural heritage.
The most evident consequence is constituted by the accentuation of the practical aspects and from the abandonment of the "theoretical tension" and the serious reflection on the matter. From the examination of the state in which pours the actual professional practice it is born the necessity to set tools able to concretely address technicians toward a more correct intervention on the pre-existences.
The scientific search, conditioned by the optics to intervene "for each case", has always investigated single monumental emergencies, unique for their intrinsic value; the results of such analyses, nevertheless, have value exclusively for the object in examination and they don't offer a wide knowledge reusable under similar conditions. Also being necessary, in the intervention on the ordinary building too, the support of diagnostics and, therefore, of the scientific search, it risks today of not to be able to use, for evident limits either of time or of expense. It has been believed opportune, therefore, to set a method of investigation that allowed the scientific search to express useful suggestions for a large number of cases.
In the historical towns, generally, inside single areas or blocks, the building adopts homogeneous constructive typologies; at times, as in the case of Ortygia, homogeneity (1) is such to be made difficult, without a careful analysis, the differentiation between the varied parts. In these zones of the town, homogeneous for historical events and constructive systems, are possible to conduct the investigations in such a way that they furnish a statistically representative sample (in our case, the façades) valid for different building unities. The variable, in this case, is constituted (skipping for an instant the separate formal characters) by the interactions between the single constructions and the surrounding environment.
It's permissible, in fact, to consider the environment and the building as any "thermodynamic system" that continuously evolves in time; the dynamics of this evolution depends on the forms of energy (thermal, chemistry, electrochemistry and mechanics) that enter in game. In the specific case, the island Ortygia is developed along an axle with course North - South; inside this territory, densely built, the Town Plan distinguishes some homogeneous parts inside which different micro-climatic conditions can be recognized. The single external walls of the constructions interact, in fact, with the environment under different thermo-hygrometric conditions.
The factors that contribute to the formation of such conditions are: the different exposure to the sun, the position in comparison to the sea and in comparison to winds, the presence and the extension of the before spaces, the height of the before buildings, the dimension of the roads and the alleys, the presence and the intensity of the vehicular traffic. The extreme variability produced by the combinations between these factors determines, on the external walls of the buildings, different effects.
The study on the systems of intervention more fit under such environmental conditions commissioned by the Provincial Association of the Industrialists of Siracusa is supported by a specific search commissioned by the Assessorato per Ortigia of the Comune di Siracusa to the "Centro C.N.R. Gino Bozza" in Milano in collaboration with other scientific institutes that are on the "Instituto Nazionale di Coordinamento Beni Culturali". (2)
This investigation, carried out on a representative sample of the façades of Ortygia, contains information that, kept in account both of the historical-typological nature of the area, and of the "material" specificities of the building components, and of the microclimatic conditions in which these components interact with the environment, helps to define the specific requirements for the techniques of intervention.
With the purpose to allow a most complete information, any technique and materials has been evaluated "fully operating"; the search, in fact, has also been conducted on interventions carried out on building samples (edited by manufacturers). On the different sampling by manufacturers, some tests have been performed related to the reliability and to the effectiveness of the single systems, evaluating, above all, if their use risk to produce occurrence of dangerous phenomena of incompatibility.
The results of the scientific investigation have allowed the layout of a "code of technical behaviours" that, using a more wide reflection in critical-methodological circle, lists the possible techniques of intervention, it suggests most correct formalities in relation to the typology and the consistence of deterioration, specifies "for each case" both merits and possible contraindications and evaluates every workmanship suggesting a set of elements of judgment regarding the following parameters: control and verification of the action, conservation of the informative content, potential reversibility, compatible behaviours with substrate, presence of collateral effects, possibility of maintenance, cost and endurance of the result.
(1) After the disastrous earthquake on the 11.01.1693, because of the collapses and to the strong damages that they have suffered, a large amount of ordinary buildings of Ortygia has been reconstructed, during the following years, with materials and techniques that make the constructive typology homogeneous.- for further details on the matter you see: AA.VV. a cura di A.Giuffrè "Sicurezza e conservazione dei centri storici -Il caso Ortigia"Roma 1993
(2) The"Istituto Nazionale di Coordinamento Beni Culturali", chairman dott. G. Alessandrini, since March 1996, functions as co-ordination of the activities of Institutes and C.N.R. Centres about conservation of national historical and artistic heritage.
